Air exchange control apparatus and system

ABSTRACT

An air exchange control apparatus to help prevent air exchange through a window in a cantilevered building alcove, comprising: forced air generation means adjacent but outside the cantilevered area; and air passage means connected at a first open end to the forced air generation means for receiving forced air, and having a second open end disposed within the cantilevered area adjacent the window, such that the forced air is directed into and across the cantilevered area in a plane generally parallel to the window.

FIELD OF THE INVENTION

The present invention relates to air exchange control devices, and more particularly to means for controlling application of said devices.

BACKGROUND OF THE INVENTION

In many industrial and commercial contexts, buildings and other constructs employ doorways or windows that open regularly throughout the day, or remain open for most of the day, such as with shipping and receiving doors at plants and warehouses. The concern raised by this practice is that air exchange can occur—conditioned air from within the building can pass through the opening, and unconditioned air from outside can enter the building. In addition, bugs and other pests have ready access through the opening. In situations where a refrigerated room is employed within a building, the same air exchange concern is evident. The cost of conditioning the air within a building or room, whether by heating or cooling that air, can be significant, and the cost of conditioning losses through the opening can accordingly also be significant.

To address this concern, it is well known to employ so-called “air curtains”. An air curtain is a device that emits a focused air stream to provide a barrier between the inside and outside environments. The air curtain configuration is controlled to provide an air velocity and direction appropriate to the particular context. In essence, the air curtain is positioned above the opening and generates a stream of air downwardly across the opening, preventing to an extent the exchange of air across the barrier formed thereby and helping to prevent pest ingress.

While the solution of air curtains has been found to be effective in many industrial and commercial contexts, a significant problem exists where the building or opening is of a non-standard configuration. For example, drive-through stations at restaurant establishments are often constructed as cantilevered rooms jutting outwardly from the main body of the building. The cantilevered room is provided with a window that opens and closes numerous times throughout the day, providing for the same air exchange problem outlined above.

FIG. 1 illustrates a prior art air curtain system applied to such a cantilevered station. The building interior 16 is provided with air conditioning means (not shown) for either heating or cooling the interior 16. The air curtain device 12 is positioned adjacent the ceiling of the building interior 16 directly above the cantilevered area 40. The air stream 22 is generated by the air curtain device 12 and is directed downwardly.

As can clearly be seen, the configuration of the drive-through station is such that the limited space does not permit the presence of an air curtain device 12 disposed directly above and adjacent the window 20. The space 18 which houses the window 20 is simply too confined to allow such an installation. Instead, the air stream 22 is directed downwardly from the ceiling along the wall from which the cantilevered station 40 juts outwardly, with the result that the air stream 22 does not provide a barrier at the window 20. The barrier is provided at a distance from the window 20, and air exchange and pest infiltration can accordingly still occur at the window location. The air curtain 12 may provide a source of air conditioning to enhance the comfort of drive-through personnel, but it does not provide the desired air exchange control. In addition, the air stream 22 may be strong enough to instead be an annoyance to those standing directly beneath the air curtain 12.

What is needed, therefore, is an air exchange control system that helps to prevent exchange at an opening in a cantilevered work area, providing a barrier that also helps to avoid pest infiltration problems.

SUMMARY OF THE INVENTION

The present invention accordingly seeks to provide an air exchange control apparatus and system that allows for proper direction and application of the forced air generated by an air curtain.

According to a first aspect of the present invention, then, there is provided an air exchange control apparatus for use with a cantilevered area having an aperture, the apparatus comprising:

forced air generation means positioned adjacent but outside the cantilevered area; and

air passage means connected at a first open end to the forced air generation means for receiving forced air therefrom, and having a second open end disposed within the cantilevered area adjacent the aperture;

such that the forced air is directed into and across the cantilevered area in a plane generally parallel to the aperture.

In exemplary embodiments of the first aspect of the present invention, the aperture preferably comprises a selectively openable window, wherein the apparatus further comprises detection means for detecting opening of the openable window, such that the opening of the openable window activates the forced air generation means. The forced air generation means preferably comprise at least one blower. The air passage means preferably comprise a plenum having a portion thereof angled into and adjacent the aperture, and the second open end preferably comprises a final portion disposed in a plane generally parallel to the aperture.

According to a second aspect of the present invention there are provided air passage means for use with a forced air source adjacent a cantilevered area having an aperture, the air passage means comprising:

a first channel for receiving forced air;

a second channel connected at a first point thereon to the first channel and for directing the forced air into the cantilevered area; and

an opening in the second channel at a second point thereon spaced from the first point, for directing the forced air across the cantilevered area in a plane generally parallel to the aperture.

In exemplary embodiments of the second aspect of the present invention, the first and second channels are preferably sealingly mated at the first point to avoid loss of forced air therefrom, and the first and second channels preferably comprise a plenum configured to mate with a forced air source. The opening preferably comprises a final portion disposed in a plane generally parallel to the aperture, and the first point is preferably at a first end of the second channel and the opening at a second end of the second channel.

According to a third aspect of the present invention there is provided an air exchange control system for use with a cantilevered area having an aperture, the system comprising:

a power source;

a forced air source outside the cantilevered area and powered by the power source;

flow direction means in communication with the forced air source for receiving and channelling forced air into the cantilevered area; and

a forced air outlet in communication with the flow direction means, adjacent to the aperture and for directing the forced air across the cantilevered area in a plane generally parallel to the aperture.

In exemplary embodiments of the third aspect of the present invention, the forced air source preferably comprises at least one blower. The flow direction means preferably comprise a generally hollow channel connected at a first open end to the forced air source and connected at a second open end to the forced air outlet. The aperture preferably comprises a selectively openable window, wherein the system further comprises detection means for detecting opening of the openable window, such that the opening of the openable window causes the power source to provide power to the forced air source. The flow direction means preferably comprise:

a first generally vertical receiving portion for transporting the forced air toward the cantilevered area; and

a second angled redirecting portion for redirecting the forced air into the cantilevered area and toward the aperture.

As can be seen, embodiments of the present invention could deliver the air flow to exactly the area it is required, providing not air conditioning but an effective air exchange barrier at the point where the exchange would normally take place. Such embodiments could prevent heat loss in the colder months and loss of air-conditioned air in the warmer months. Employee health and comfort are enhanced by preventing exposure to cold exterior air, while the barrier is provided at the location where flying insects would otherwise be able to enter the building interior.

A detailed description of an exemplary embodiment of the present invention is given in the following. It is to be understood, however, that the invention is not to be construed as limited to this embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings, which illustrate an exemplary embodiment of the present invention:

FIG. 1 is a prior art air curtain system as presently applied to cantilevered work stations;

FIG. 2 is a simplified side elevation view illustrating the positioning of an air exchange control apparatus according to the present invention;

FIG. 3 is an embodiment of a plenum according to the present invention; and

FIG. 4 provides detailed elevation and top plan views of a discharge vane.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENT

Referring now in detail to the accompanying drawings, there is illustrated an exemplary embodiment of an air exchange control apparatus and system according to the present invention, generally referred to by the numeral 10.

Referring now to FIG. 2, the air exchange control apparatus and system 10 comprises an air curtain device 12 and a plenum 14, the plenum 14 being variously referred to as air passage means and flow direction means herein. The air curtain device 12 preferably comprises at least one blower (not shown) to generate forced air, and can be selected from any number of commercially available products, but is preferably an ENERGYGUARD 4009-CEA provided by Advanced Energy Solutions Inc. of Calgary, Alberta, Canada, the present applicant. The air curtain device 12 is positioned at or near the ceiling of the building interior 16, near the location of the cantilevered area 40 which is provided with a selectively openable window 20. The plenum 14 mates with the air curtain device 12 and extends along the building wall and into the cantilevered area interior 18, allowing the air stream 22 to enter the cantilevered area interior 18 directly adjacent the window 20.

Referring now to FIG. 3, the plenum 14 is illustrated in detail. The plenum 14 comprises a first open end 24 for mating with the air curtain device 12. When the air curtain device 12 generates forced air, the plenum 14 receives the forced air in a first channel 30, also referred to as a receiving portion of the plenum 14. The first channel 30 is sealingly mated to a second channel 32 to prevent loss of air pressure at the juncture point. The second channel 32, also referred to as the redirecting portion, receives the forced air from the first channel 30 and redirects the forced air into the cantilevered area interior 18. The first channel 30 is generally vertical to follow the interior wall of the building interior 16, but may be off-vertical given differing wall orientation or obstacles between the ceiling and the cantilevered area 40. The second channel 32 is angled as necessary to redirect the forced air toward an edge of the window 20.

In the illustrated embodiment, the second channel 32 connects to a final portion 38, which includes a second open end 26 for releasing forced air adjacent the window 20. The final portion 38 contains a discharge vane 28 centred therein for aiding in the direction of the forced air adjacent the window 20. The final portion 38 is preferably disposed in an orientation parallel to that of the window 20, to assist in providing an effective barrier.

The plenum 14 is preferably composed of ¼ inch clear Plexiglas™ or similar material. The first open end 24 is sized and configured to mate with the air curtain device 12, and in the illustrated embodiment the first channel 30 then gradually tapers toward the second channel 32. Mounting of the plenum 14 is achieved by means of mounting flanges 34 manufactured as part of the plenum 14, which flanges 34 contain mounting holes 36 for receiving screws (not shown). As can be seen in FIG. 2, the mounting could accordingly take place against the vertical wall surface, not requiring additional securing means on the cantilevered area 40 inner surface in the event that such is composed of glass or other similar material common in such cantilevered stations.

The discharge vane 28 is illustrated in detail in FIG. 4. The vane 28 is a generally flat and elongate sheet that is disposed within the final portion 38 of the plenum 14. The vane 28 is provided with brackets 44 at each end to enable mounting on the inner surfaces of the final portion 38. Screws 42 pass through the brackets 44 and the final portion 38 walls, and can be secured using wing nuts (not shown). This means of securing the vane 28 within the final portion 38 also allows for adjusting the angle of the vane 28 relative to the window 20, enabling greater flexibility in forced air flow redirection. For example, in the event that exterior wind is being directed against the window, which could disrupt the barrier generated by the present invention, angling the discharge vane 28 toward the exterior directs the forced air against the wind and helps to ensure a barrier generally parallel to the window opening 20.

The air curtain device 12 requires a power source (not shown) to power the blower(s). Given energy consumption and the reality that an air barrier will not be required when the window 20 is closed, it is possible to provide the system 10 with detection means (not shown) for detecting the opening of the window 20. As would be obvious to one skilled in the art, various means are available to allow the selective powering of the air curtain device 12, such that the air curtain device 12 only operates when the detection means detect the opening of the window 20. This would reduce energy consumption and any noise that might be associated with operation of the selected air curtain device 12.

While a particular embodiment of the present invention has been described in the foregoing, it is to be understood that other embodiments are possible within the scope of the invention and are intended to be included herein. It will be clear to any person skilled in the art that modifications of and adjustments to this invention, not shown, are possible without departing from the spirit of the invention as demonstrated through the exemplary embodiment. The invention is therefore to be considered limited solely by the scope of the appended claims. 

1. An air exchange control apparatus for use with a cantilevered area having an aperture, the apparatus comprising: forced air generation means positioned adjacent but outside the cantilevered area; and air passage means connected at a first open end to the forced air generation means for receiving forced air therefrom, and having a second open end disposed within the cantilevered area adjacent the aperture; such that the forced air is directed into and across the cantilevered area in a plane generally parallel to the aperture.
 2. Air passage means for use with a forced air source adjacent a cantilevered area having an aperture, the air passage means comprising: a first channel for receiving forced air; a second channel connected at a first point thereon to the first channel and for directing the forced air into the cantilevered area; and an opening in the second channel at a second point thereon spaced from the first point, for directing the forced air across the cantilevered area in a plane generally parallel to the aperture.
 3. An air exchange control system for use with a cantilevered area having an aperture, the system comprising: a power source; a forced air source outside the cantilevered area and powered by the power source; flow direction means in communication with the forced air source for receiving and channelling forced air into the cantilevered area; and a forced air outlet in communication with the flow direction means, adjacent to the aperture and for directing the forced air across the cantilevered area in a plane generally parallel to the aperture.
 4. The air exchange control apparatus of claim 1 wherein the aperture comprises a selectively openable window, wherein the apparatus further comprises detection means for detecting opening of the openable window, such that the opening of the openable window activates the forced air generation means.
 5. The air exchange control apparatus of claim 1 wherein the forced air generation means comprise at least one blower.
 6. The air exchange control apparatus of claim 1 wherein the air passage means comprise a plenum having a portion thereof angled into and adjacent the aperture.
 7. The air exchange control apparatus of claim 1 wherein the second open end comprises a final portion disposed in a plane generally parallel to the aperture.
 8. The air passage means of claim 2 wherein the first and second channels are sealingly mated at the first point to avoid loss of forced air therefrom.
 9. The air passage means of claim 2 wherein the first and second channels comprise a plenum configured to mate with a forced air source.
 10. The air passage means of claim 2 wherein the opening comprises a final portion disposed in a plane generally parallel to the aperture.
 11. The air passage means of claim 2 wherein the first point is at a first end of the second channel and the opening is at a second end of the second channel.
 12. The air exchange control system of claim 3 wherein the forced air source comprises at least one blower.
 13. The air exchange control system of claim 3 wherein the flow direction means comprise a generally hollow channel connected at a first open end to the forced air source and connected at a second open end to the forced air outlet.
 14. The air exchange control system of claim 3 wherein the flow direction means comprise: a first generally vertical receiving portion for transporting the forced air toward the cantilevered area; and a second angled redirecting portion for redirecting the forced air into the cantilevered area and toward the aperture.
 15. The air exchange control system of claim 3 wherein the aperture comprises a selectively openable window, wherein the system further comprises detection means for detecting opening of the openable window, such that the opening of the openable window causes the power source to provide power to the forced air source. 